Subtract 24/28 from 21/42
21/42 - 24/28 is -5/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
24/28 = 24 × 3/28 × 3 = 72/84 - Subtract the two like fractions:
42/84 - 72/84 = 42 - 72/84 = -30/84 - After reducing the fraction, the answer is -5/14
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